1 /*
2 * Emma Mobile GPIO Support - GIO
3 *
4 * Copyright (C) 2012 Magnus Damm
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20 #include <linux/init.h>
21 #include <linux/platform_device.h>
22 #include <linux/spinlock.h>
23 #include <linux/interrupt.h>
24 #include <linux/ioport.h>
25 #include <linux/io.h>
26 #include <linux/irq.h>
27 #include <linux/irqdomain.h>
28 #include <linux/bitops.h>
29 #include <linux/err.h>
30 #include <linux/gpio.h>
31 #include <linux/slab.h>
32 #include <linux/module.h>
33 #include <linux/platform_data/gpio-em.h>
34
35 struct em_gio_priv {
36 void __iomem *base0;
37 void __iomem *base1;
38 spinlock_t sense_lock;
39 struct platform_device *pdev;
40 struct gpio_chip gpio_chip;
41 struct irq_chip irq_chip;
42 struct irq_domain *irq_domain;
43 };
44
45 #define GIO_E1 0x00
46 #define GIO_E0 0x04
47 #define GIO_EM 0x04
48 #define GIO_OL 0x08
49 #define GIO_OH 0x0c
50 #define GIO_I 0x10
51 #define GIO_IIA 0x14
52 #define GIO_IEN 0x18
53 #define GIO_IDS 0x1c
54 #define GIO_IIM 0x1c
55 #define GIO_RAW 0x20
56 #define GIO_MST 0x24
57 #define GIO_IIR 0x28
58
59 #define GIO_IDT0 0x40
60 #define GIO_IDT1 0x44
61 #define GIO_IDT2 0x48
62 #define GIO_IDT3 0x4c
63 #define GIO_RAWBL 0x50
64 #define GIO_RAWBH 0x54
65 #define GIO_IRBL 0x58
66 #define GIO_IRBH 0x5c
67
68 #define GIO_IDT(n) (GIO_IDT0 + ((n) * 4))
69
em_gio_read(struct em_gio_priv * p,int offs)70 static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs)
71 {
72 if (offs < GIO_IDT0)
73 return ioread32(p->base0 + offs);
74 else
75 return ioread32(p->base1 + (offs - GIO_IDT0));
76 }
77
em_gio_write(struct em_gio_priv * p,int offs,unsigned long value)78 static inline void em_gio_write(struct em_gio_priv *p, int offs,
79 unsigned long value)
80 {
81 if (offs < GIO_IDT0)
82 iowrite32(value, p->base0 + offs);
83 else
84 iowrite32(value, p->base1 + (offs - GIO_IDT0));
85 }
86
em_gio_irq_disable(struct irq_data * d)87 static void em_gio_irq_disable(struct irq_data *d)
88 {
89 struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
90
91 em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d)));
92 }
93
em_gio_irq_enable(struct irq_data * d)94 static void em_gio_irq_enable(struct irq_data *d)
95 {
96 struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
97
98 em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d)));
99 }
100
101 #define GIO_ASYNC(x) (x + 8)
102
103 static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
104 [IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00),
105 [IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01),
106 [IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02),
107 [IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03),
108 [IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04),
109 };
110
em_gio_irq_set_type(struct irq_data * d,unsigned int type)111 static int em_gio_irq_set_type(struct irq_data *d, unsigned int type)
112 {
113 unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK];
114 struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
115 unsigned int reg, offset, shift;
116 unsigned long flags;
117 unsigned long tmp;
118
119 if (!value)
120 return -EINVAL;
121
122 offset = irqd_to_hwirq(d);
123
124 pr_debug("gio: sense irq = %d, mode = %d\n", offset, value);
125
126 /* 8 x 4 bit fields in 4 IDT registers */
127 reg = GIO_IDT(offset >> 3);
128 shift = (offset & 0x07) << 4;
129
130 spin_lock_irqsave(&p->sense_lock, flags);
131
132 /* disable the interrupt in IIA */
133 tmp = em_gio_read(p, GIO_IIA);
134 tmp &= ~BIT(offset);
135 em_gio_write(p, GIO_IIA, tmp);
136
137 /* change the sense setting in IDT */
138 tmp = em_gio_read(p, reg);
139 tmp &= ~(0xf << shift);
140 tmp |= value << shift;
141 em_gio_write(p, reg, tmp);
142
143 /* clear pending interrupts */
144 em_gio_write(p, GIO_IIR, BIT(offset));
145
146 /* enable the interrupt in IIA */
147 tmp = em_gio_read(p, GIO_IIA);
148 tmp |= BIT(offset);
149 em_gio_write(p, GIO_IIA, tmp);
150
151 spin_unlock_irqrestore(&p->sense_lock, flags);
152
153 return 0;
154 }
155
em_gio_irq_handler(int irq,void * dev_id)156 static irqreturn_t em_gio_irq_handler(int irq, void *dev_id)
157 {
158 struct em_gio_priv *p = dev_id;
159 unsigned long pending;
160 unsigned int offset, irqs_handled = 0;
161
162 while ((pending = em_gio_read(p, GIO_MST))) {
163 offset = __ffs(pending);
164 em_gio_write(p, GIO_IIR, BIT(offset));
165 generic_handle_irq(irq_find_mapping(p->irq_domain, offset));
166 irqs_handled++;
167 }
168
169 return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
170 }
171
gpio_to_priv(struct gpio_chip * chip)172 static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip)
173 {
174 return container_of(chip, struct em_gio_priv, gpio_chip);
175 }
176
em_gio_direction_input(struct gpio_chip * chip,unsigned offset)177 static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset)
178 {
179 em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset));
180 return 0;
181 }
182
em_gio_get(struct gpio_chip * chip,unsigned offset)183 static int em_gio_get(struct gpio_chip *chip, unsigned offset)
184 {
185 return (int)(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset));
186 }
187
__em_gio_set(struct gpio_chip * chip,unsigned int reg,unsigned shift,int value)188 static void __em_gio_set(struct gpio_chip *chip, unsigned int reg,
189 unsigned shift, int value)
190 {
191 /* upper 16 bits contains mask and lower 16 actual value */
192 em_gio_write(gpio_to_priv(chip), reg,
193 (1 << (shift + 16)) | (value << shift));
194 }
195
em_gio_set(struct gpio_chip * chip,unsigned offset,int value)196 static void em_gio_set(struct gpio_chip *chip, unsigned offset, int value)
197 {
198 /* output is split into two registers */
199 if (offset < 16)
200 __em_gio_set(chip, GIO_OL, offset, value);
201 else
202 __em_gio_set(chip, GIO_OH, offset - 16, value);
203 }
204
em_gio_direction_output(struct gpio_chip * chip,unsigned offset,int value)205 static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset,
206 int value)
207 {
208 /* write GPIO value to output before selecting output mode of pin */
209 em_gio_set(chip, offset, value);
210 em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset));
211 return 0;
212 }
213
em_gio_to_irq(struct gpio_chip * chip,unsigned offset)214 static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset)
215 {
216 return irq_create_mapping(gpio_to_priv(chip)->irq_domain, offset);
217 }
218
em_gio_irq_domain_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hw)219 static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int virq,
220 irq_hw_number_t hw)
221 {
222 struct em_gio_priv *p = h->host_data;
223
224 pr_debug("gio: map hw irq = %d, virq = %d\n", (int)hw, virq);
225
226 irq_set_chip_data(virq, h->host_data);
227 irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq);
228 set_irq_flags(virq, IRQF_VALID); /* kill me now */
229 return 0;
230 }
231
232 static struct irq_domain_ops em_gio_irq_domain_ops = {
233 .map = em_gio_irq_domain_map,
234 .xlate = irq_domain_xlate_twocell,
235 };
236
em_gio_probe(struct platform_device * pdev)237 static int em_gio_probe(struct platform_device *pdev)
238 {
239 struct gpio_em_config pdata_dt;
240 struct gpio_em_config *pdata = pdev->dev.platform_data;
241 struct em_gio_priv *p;
242 struct resource *io[2], *irq[2];
243 struct gpio_chip *gpio_chip;
244 struct irq_chip *irq_chip;
245 const char *name = dev_name(&pdev->dev);
246 int ret;
247
248 p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
249 if (!p) {
250 dev_err(&pdev->dev, "failed to allocate driver data\n");
251 ret = -ENOMEM;
252 goto err0;
253 }
254
255 p->pdev = pdev;
256 platform_set_drvdata(pdev, p);
257 spin_lock_init(&p->sense_lock);
258
259 io[0] = platform_get_resource(pdev, IORESOURCE_MEM, 0);
260 io[1] = platform_get_resource(pdev, IORESOURCE_MEM, 1);
261 irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
262 irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
263
264 if (!io[0] || !io[1] || !irq[0] || !irq[1]) {
265 dev_err(&pdev->dev, "missing IRQ or IOMEM\n");
266 ret = -EINVAL;
267 goto err0;
268 }
269
270 p->base0 = devm_ioremap_nocache(&pdev->dev, io[0]->start,
271 resource_size(io[0]));
272 if (!p->base0) {
273 dev_err(&pdev->dev, "failed to remap low I/O memory\n");
274 ret = -ENXIO;
275 goto err0;
276 }
277
278 p->base1 = devm_ioremap_nocache(&pdev->dev, io[1]->start,
279 resource_size(io[1]));
280 if (!p->base1) {
281 dev_err(&pdev->dev, "failed to remap high I/O memory\n");
282 ret = -ENXIO;
283 goto err0;
284 }
285
286 if (!pdata) {
287 memset(&pdata_dt, 0, sizeof(pdata_dt));
288 pdata = &pdata_dt;
289
290 if (of_property_read_u32(pdev->dev.of_node, "ngpios",
291 &pdata->number_of_pins)) {
292 dev_err(&pdev->dev, "Missing ngpios OF property\n");
293 ret = -EINVAL;
294 goto err0;
295 }
296
297 ret = of_alias_get_id(pdev->dev.of_node, "gpio");
298 if (ret < 0) {
299 dev_err(&pdev->dev, "Couldn't get OF id\n");
300 goto err0;
301 }
302 pdata->gpio_base = ret * 32; /* 32 GPIOs per instance */
303 }
304
305 gpio_chip = &p->gpio_chip;
306 gpio_chip->direction_input = em_gio_direction_input;
307 gpio_chip->get = em_gio_get;
308 gpio_chip->direction_output = em_gio_direction_output;
309 gpio_chip->set = em_gio_set;
310 gpio_chip->to_irq = em_gio_to_irq;
311 gpio_chip->label = name;
312 gpio_chip->owner = THIS_MODULE;
313 gpio_chip->base = pdata->gpio_base;
314 gpio_chip->ngpio = pdata->number_of_pins;
315
316 irq_chip = &p->irq_chip;
317 irq_chip->name = name;
318 irq_chip->irq_mask = em_gio_irq_disable;
319 irq_chip->irq_unmask = em_gio_irq_enable;
320 irq_chip->irq_enable = em_gio_irq_enable;
321 irq_chip->irq_disable = em_gio_irq_disable;
322 irq_chip->irq_set_type = em_gio_irq_set_type;
323 irq_chip->flags = IRQCHIP_SKIP_SET_WAKE;
324
325 p->irq_domain = irq_domain_add_simple(pdev->dev.of_node,
326 pdata->number_of_pins,
327 pdata->irq_base,
328 &em_gio_irq_domain_ops, p);
329 if (!p->irq_domain) {
330 ret = -ENXIO;
331 dev_err(&pdev->dev, "cannot initialize irq domain\n");
332 goto err0;
333 }
334
335 if (devm_request_irq(&pdev->dev, irq[0]->start,
336 em_gio_irq_handler, 0, name, p)) {
337 dev_err(&pdev->dev, "failed to request low IRQ\n");
338 ret = -ENOENT;
339 goto err1;
340 }
341
342 if (devm_request_irq(&pdev->dev, irq[1]->start,
343 em_gio_irq_handler, 0, name, p)) {
344 dev_err(&pdev->dev, "failed to request high IRQ\n");
345 ret = -ENOENT;
346 goto err1;
347 }
348
349 ret = gpiochip_add(gpio_chip);
350 if (ret) {
351 dev_err(&pdev->dev, "failed to add GPIO controller\n");
352 goto err1;
353 }
354 return 0;
355
356 err1:
357 irq_domain_remove(p->irq_domain);
358 err0:
359 return ret;
360 }
361
em_gio_remove(struct platform_device * pdev)362 static int em_gio_remove(struct platform_device *pdev)
363 {
364 struct em_gio_priv *p = platform_get_drvdata(pdev);
365 int ret;
366
367 ret = gpiochip_remove(&p->gpio_chip);
368 if (ret)
369 return ret;
370
371 irq_domain_remove(p->irq_domain);
372 return 0;
373 }
374
375 static const struct of_device_id em_gio_dt_ids[] = {
376 { .compatible = "renesas,em-gio", },
377 {},
378 };
379 MODULE_DEVICE_TABLE(of, em_gio_dt_ids);
380
381 static struct platform_driver em_gio_device_driver = {
382 .probe = em_gio_probe,
383 .remove = em_gio_remove,
384 .driver = {
385 .name = "em_gio",
386 .of_match_table = em_gio_dt_ids,
387 .owner = THIS_MODULE,
388 }
389 };
390
em_gio_init(void)391 static int __init em_gio_init(void)
392 {
393 return platform_driver_register(&em_gio_device_driver);
394 }
395 postcore_initcall(em_gio_init);
396
em_gio_exit(void)397 static void __exit em_gio_exit(void)
398 {
399 platform_driver_unregister(&em_gio_device_driver);
400 }
401 module_exit(em_gio_exit);
402
403 MODULE_AUTHOR("Magnus Damm");
404 MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver");
405 MODULE_LICENSE("GPL v2");
406